From fa981fc945e7995aef0e828cfbce3cfda87bfe04 Mon Sep 17 00:00:00 2001
From: "Zeeshan Ali (Khattak)" <zeeshanak@gnome.org>
Date: Tue, 24 Jan 2012 04:26:18 +0200
Subject: [PATCH] Allow custom metadata in domain configuration XML

Applications can now insert custom nodes and hierarchies into domain
configuration XML. Although currently not enforced, applications are
required to use their own namespaces on every custom node they insert,
with only one top-level element per namespace.
---
 AUTHORS                                       |  1 +
 docs/formatdomain.html.in                     | 20 ++++++++++
 docs/schemas/domaincommon.rng                 | 26 +++++++++++++
 src/conf/domain_conf.c                        | 38 +++++++++++++++++++
 src/conf/domain_conf.h                        |  3 ++
 tests/domainsnapshotxml2xmlout/metadata.xml   | 38 +++++++++++++++++++
 tests/domainsnapshotxml2xmltest.c             |  1 +
 .../qemuxml2argv-metadata.args                |  4 ++
 .../qemuxml2argv-metadata.xml                 | 30 +++++++++++++++
 .../qemuxml2xmlout-metadata.xml               | 29 ++++++++++++++
 tests/qemuxml2xmltest.c                       |  2 +
 11 files changed, 192 insertions(+)
 create mode 100644 tests/domainsnapshotxml2xmlout/metadata.xml
 create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-metadata.args
 create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-metadata.xml
 create mode 100644 tests/qemuxml2xmloutdata/qemuxml2xmlout-metadata.xml

diff --git a/AUTHORS b/AUTHORS
index 783c48a16e..f383c660ab 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -217,6 +217,7 @@ Patches have also been contributed by:
   Deepak C Shetty      <deepakcs@linux.vnet.ibm.com>
   Martin Kletzander    <mkletzan@redhat.com>
   Laszlo Ersek         <lersek@redhat.com>
+  Zeeshan Ali (Khattak) <zeeshanak@gnome.org>
 
   [....send patches to get your name here....]
 
diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index 6667bed6b5..6b025e8564 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -3556,6 +3556,26 @@ qemu-kvm -net nic,model=? /dev/null
       sub-element <code>label</code> are supported.
     </p>
 
+    <h3><a name="customMetadata">Custom metadata</a></h3>
+
+<pre>
+  ...
+  &lt;metadata&gt;
+    &lt;app1:foo xmlns:app1="http://app1.org/app1/"&gt;..&lt;/app1:foo&gt;
+    &lt;app2:bar xmlns:app2="http://app1.org/app2/"&gt;..&lt;/app2:bar&gt;
+  &lt;/metadata&gt;
+  ...</pre>
+
+    <dl>
+      <dt><code>metadata</code></dt>
+      <dd>The <code>metadata</code> node can be used by applications to
+      store custom metadata in the form of XML nodes/trees. Applications
+      must use custom namespaces on their XML nodes/trees, with only
+      one top-level element per namespace (if the application needs
+      structure, they should have sub-elements to their namespace
+      element). <span class="since">Since 0.9.10</span></dd>
+    </dl>
+
     <h2><a name="examples">Example configs</a></h2>
 
     <p>
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index 2041dfbbc2..4fa968dc43 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -25,6 +25,9 @@
         <optional>
           <ref name="description"/>
         </optional>
+        <optional>
+          <ref name="metadata"/>
+        </optional>
         <optional>
           <ref name="cpu"/>
         </optional>
@@ -2942,6 +2945,29 @@
     </element>
   </define>
 
+  <define name="metadata">
+    <element name="metadata">
+      <zeroOrMore>
+        <ref name="customElement"/>
+      </zeroOrMore>
+    </element>
+  </define>
+
+  <define name="customElement">
+    <element>
+      <anyName/>
+      <zeroOrMore>
+        <choice>
+          <attribute>
+            <anyName/>
+          </attribute>
+          <text/>
+          <ref name="customElement"/>
+        </choice>
+      </zeroOrMore>
+    </element>
+  </define>
+
   <!--
        Type library
 
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 8eed85b61a..f2c8d02171 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -1500,6 +1500,8 @@ void virDomainDefFree(virDomainDefPtr def)
     if (def->namespaceData && def->ns.free)
         (def->ns.free)(def->namespaceData);
 
+    xmlFreeNode(def->metadata);
+
     VIR_FREE(def);
 }
 
@@ -8072,6 +8074,11 @@ static virDomainDefPtr virDomainDefParseXML(virCapsPtr caps,
         def->os.smbios_mode = VIR_DOMAIN_SMBIOS_NONE; /* not present */
     }
 
+    /* Extract custom metadata */
+    if ((node = virXPathNode("./metadata[1]", ctxt)) != NULL) {
+        def->metadata = xmlCopyNode(node, 1);
+    }
+
     /* we have to make a copy of all of the callback pointers here since
      * we won't have the virCaps structure available during free
      */
@@ -8211,6 +8218,7 @@ virDomainDefParse(const char *xmlStr,
 {
     xmlDocPtr xml;
     virDomainDefPtr def = NULL;
+    int keepBlanksDefault = xmlKeepBlanksDefault(0);
 
     if ((xml = virXMLParse(filename, xmlStr, _("(domain_definition)")))) {
         def = virDomainDefParseNode(caps, xml, xmlDocGetRootElement(xml),
@@ -8218,6 +8226,7 @@ virDomainDefParse(const char *xmlStr,
         xmlFreeDoc(xml);
     }
 
+    xmlKeepBlanksDefault(keepBlanksDefault);
     return def;
 }
 
@@ -8311,6 +8320,7 @@ virDomainObjParseFile(virCapsPtr caps,
 {
     xmlDocPtr xml;
     virDomainObjPtr obj = NULL;
+    int keepBlanksDefault = xmlKeepBlanksDefault(0);
 
     if ((xml = virXMLParseFile(filename))) {
         obj = virDomainObjParseNode(caps, xml,
@@ -8319,6 +8329,7 @@ virDomainObjParseFile(virCapsPtr caps,
         xmlFreeDoc(xml);
     }
 
+    xmlKeepBlanksDefault(keepBlanksDefault);
     return obj;
 }
 
@@ -11833,6 +11844,30 @@ virDomainDefFormatInternal(virDomainDefPtr def,
             goto cleanup;
     }
 
+    /* Custom metadata comes at the end */
+    if (def->metadata) {
+        xmlBufferPtr xmlbuf;
+        int oldIndentTreeOutput = xmlIndentTreeOutput;
+
+        /* Indentation on output requires that we previously set
+         * xmlKeepBlanksDefault to 0 when parsing; also, libxml does 2
+         * spaces per level of indentation of intermediate elements,
+         * but no leading indentation before the starting element.
+         * Thankfully, libxml maps what looks like globals into
+         * thread-local uses, so we are thread-safe.  */
+        xmlIndentTreeOutput = 1;
+        xmlbuf = xmlBufferCreate();
+        if (xmlNodeDump(xmlbuf, def->metadata->doc, def->metadata,
+                        virBufferGetIndent(buf, false) / 2 + 1, 1) < 0) {
+            xmlBufferFree(xmlbuf);
+            xmlIndentTreeOutput = oldIndentTreeOutput;
+            goto cleanup;
+        }
+        virBufferAsprintf(buf, "  %s\n", (char *) xmlBufferContent(xmlbuf));
+        xmlBufferFree(xmlbuf);
+        xmlIndentTreeOutput = oldIndentTreeOutput;
+    }
+
     virBufferAddLit(buf, "</domain>\n");
 
     if (virBufferError(buf))
@@ -12517,11 +12552,14 @@ virDomainSnapshotDefParseString(const char *xmlStr,
     struct timeval tv;
     int active;
     char *tmp;
+    int keepBlanksDefault = xmlKeepBlanksDefault(0);
 
     xml = virXMLParseCtxt(NULL, xmlStr, _("(domain_snapshot)"), &ctxt);
     if (!xml) {
+        xmlKeepBlanksDefault(keepBlanksDefault);
         return NULL;
     }
+    xmlKeepBlanksDefault(keepBlanksDefault);
 
     if (VIR_ALLOC(def) < 0) {
         virReportOOMError();
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index a49795cdda..3b522a9a28 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -1525,6 +1525,9 @@ struct _virDomainDef {
 
     void *namespaceData;
     virDomainXMLNamespace ns;
+
+    /* Application-specific custom metadata */
+    xmlNodePtr metadata;
 };
 
 enum virDomainTaintFlags {
diff --git a/tests/domainsnapshotxml2xmlout/metadata.xml b/tests/domainsnapshotxml2xmlout/metadata.xml
new file mode 100644
index 0000000000..45180c9c59
--- /dev/null
+++ b/tests/domainsnapshotxml2xmlout/metadata.xml
@@ -0,0 +1,38 @@
+<domainsnapshot>
+  <name>my snap name</name>
+  <description>!@#$%^</description>
+  <state>running</state>
+  <parent>
+    <name>earlier_snap</name>
+  </parent>
+  <creationTime>1272917631</creationTime>
+  <domain type='qemu'>
+    <name>QEMUGuest1</name>
+    <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+    <memory>219100</memory>
+    <currentMemory>219100</currentMemory>
+    <vcpu cpuset='1-4,8-20,525'>1</vcpu>
+    <os>
+      <type arch='i686' machine='pc'>hvm</type>
+      <boot dev='hd'/>
+    </os>
+    <clock offset='utc'/>
+    <on_poweroff>destroy</on_poweroff>
+    <on_reboot>restart</on_reboot>
+    <on_crash>destroy</on_crash>
+    <devices>
+      <emulator>/usr/bin/qemu</emulator>
+      <disk type='block' device='disk'>
+        <source dev='/dev/HostVG/QEMUGuest1'/>
+        <target dev='hda' bus='ide'/>
+        <address type='drive' controller='0' bus='0' unit='0'/>
+      </disk>
+      <controller type='ide' index='0'/>
+      <memballoon model='virtio'/>
+    </devices>
+    <metadata>
+      <app1:foo xmlns:app1="http://foo.org/">fooish</app1:foo>
+      <app2:bar xmlns:app2="http://bar.com/" maman="baz">barish</app2:bar>
+    </metadata>
+  </domain>
+</domainsnapshot>
diff --git a/tests/domainsnapshotxml2xmltest.c b/tests/domainsnapshotxml2xmltest.c
index 90ff9bb372..5c2e670231 100644
--- a/tests/domainsnapshotxml2xmltest.c
+++ b/tests/domainsnapshotxml2xmltest.c
@@ -109,6 +109,7 @@ mymain(void)
     DO_TEST("noparent_nodescription_noactive", NULL, 0);
     DO_TEST("noparent_nodescription", NULL, 1);
     DO_TEST("noparent", "9d37b878-a7cc-9f9a-b78f-49b3abad25a8", 0);
+    DO_TEST("metadata", "c7a5fdbd-edaf-9455-926a-d65c16db1809", 0);
 
     virCapabilitiesFree(driver.caps);
 
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-metadata.args b/tests/qemuxml2argvdata/qemuxml2argv-metadata.args
new file mode 100644
index 0000000000..651793da96
--- /dev/null
+++ b/tests/qemuxml2argvdata/qemuxml2argv-metadata.args
@@ -0,0 +1,4 @@
+LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test /usr/bin/qemu -S -M \
+pc -m 214 -smp 1 -name QEMUGuest1 -nographic -monitor unix:/tmp/test-monitor,\
+server,nowait -no-acpi -boot c -hda /dev/HostVG/QEMUGuest1 -net none -serial \
+none -parallel none -usb
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-metadata.xml b/tests/qemuxml2argvdata/qemuxml2argv-metadata.xml
new file mode 100644
index 0000000000..b0f90dd72c
--- /dev/null
+++ b/tests/qemuxml2argvdata/qemuxml2argv-metadata.xml
@@ -0,0 +1,30 @@
+<domain type='qemu'>
+  <name>QEMUGuest1</name>
+  <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+  <memory>219100</memory>
+  <currentMemory>219100</currentMemory>
+  <vcpu cpuset='1-4,8-20,525'>1</vcpu>
+  <os>
+    <type arch='i686' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu</emulator>
+    <disk type='block' device='disk'>
+      <source dev='/dev/HostVG/QEMUGuest1'/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' unit='0'/>
+    </disk>
+    <controller type='ide' index='0'/>
+    <memballoon model='virtio'/>
+  </devices>
+  <!-- intentional mis-indentation -->
+  <metadata>
+      <app1:foo xmlns:app1="http://foo.org/">fooish</app1:foo>
+  <app2:bar xmlns:app2="http://bar.com/" maman="baz">barish</app2:bar>
+  </metadata>
+</domain>
diff --git a/tests/qemuxml2xmloutdata/qemuxml2xmlout-metadata.xml b/tests/qemuxml2xmloutdata/qemuxml2xmlout-metadata.xml
new file mode 100644
index 0000000000..a6888ee3ae
--- /dev/null
+++ b/tests/qemuxml2xmloutdata/qemuxml2xmlout-metadata.xml
@@ -0,0 +1,29 @@
+<domain type='qemu'>
+  <name>QEMUGuest1</name>
+  <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+  <memory>219100</memory>
+  <currentMemory>219100</currentMemory>
+  <vcpu cpuset='1-4,8-20,525'>1</vcpu>
+  <os>
+    <type arch='i686' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu</emulator>
+    <disk type='block' device='disk'>
+      <source dev='/dev/HostVG/QEMUGuest1'/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' unit='0'/>
+    </disk>
+    <controller type='ide' index='0'/>
+    <memballoon model='virtio'/>
+  </devices>
+  <metadata>
+    <app1:foo xmlns:app1="http://foo.org/">fooish</app1:foo>
+    <app2:bar xmlns:app2="http://bar.com/" maman="baz">barish</app2:bar>
+  </metadata>
+</domain>
diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c
index 293c2a7d5f..df317fd538 100644
--- a/tests/qemuxml2xmltest.c
+++ b/tests/qemuxml2xmltest.c
@@ -210,6 +210,8 @@ mymain(void)
     DO_TEST_DIFFERENT("graphics-listen-network2");
     DO_TEST_DIFFERENT("graphics-spice-timeout");
 
+    DO_TEST_DIFFERENT("metadata");
+
     virCapabilitiesFree(driver.caps);
 
     return (ret==0 ? EXIT_SUCCESS : EXIT_FAILURE);